--------------------+-------+-------+------+-------+--------+-------- Hours worked | 2 | 4 | 6 | 8 | 10 | 12 Grammes of chlorine | | | | | | per litre produced| 4·35 | 7·38 | 9·9 | 12·42 | 14·31 | 16·20 Temperature C. of | | | | | | brine during | | | | | | operation | 20 | 21 | 20 | 21 | 20 | 20 Ampères of 110 volts| 55 | 50 | 46 | 52 | 47 | 43 Power in h.p. hours | 16 | 31 | 45 | 61 | 75 | 89 Cost of the h.p. at | | | | | | ·22_d._ per h.p. | | | |1_s._ |1_s._ |1_s._ hour | 3½_d._| 6¾_d._|10_d._| 1½_d._| 4½_d._| 7½_d._ Cost of salt |1_s._ |1_s._ |1_s._ |1_s._ |1_s._ |1_s._ | 6_d._| 6_d._| 6_d._| 6_d._ | 6_d._ | 6_d._ Total cost |1_s._ |2_s._ |2_s._ |2_s._ |2_s._ |3_s._ | 9½_d._| 0¾_d._| 4_d._| 7½_d._| 10½_d._| 1½_d._ Total chlorine | | | | | | obtained in kilos.| 3·262 | 5·535 | 7·425| 9·315 | 10·732 | 12·150 Cost of chlorine per| | | | | | kilo. |6·6_d._| 4½_d._|3¾_d._|3·4_d._| 3·2_d._| 3_d._ Salt used per kilo. | | | | | | chlorine | 35 | 20 | 15 | 12 | 10 | 9 --------------------+-------+-------+------+-------+--------+-------- The above costs have been estimated on prices as follows:-- Coal 10_s._ per ton. Salt 12_s._ per ton. After 12 hours the 166 gallons (750 litres) are converted into electrolytic bleach liquor containing 26¾ lbs. of active chlorine (12·15 kilos.). _Beating._--Although the rags are reduced by the breaking engine to a condition of fibrous lint, called "half-stuff," they are not fit for conversion into paper. They have to be _beaten_ in special machinery until a complete separation of the single fibres has been effected, and this process is rightly regarded by many paper-makers as the most important stage of manufacture. [Illustration: FIG. 12.--Oettel and Haas' Apparatus for the manufacture of Electrolytic Bleach Liquor.] The beating engine is similar in construction to the breaking engine, but there are certain essential differences in arrangement and manipulation. There is usually no drum-washer; the roll contains a large number of knives which are fixed in clumps or sets of three round the circumference; the lowering of the roll upon the bed-plate is carefully watched and controlled, and the desired effects are only obtained by strict attention to the condition of the pulp during the whole process. [Illustration: FIG. 13.--The "Hollander" Beating Engine.]